(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Consider a system comprising two extended bodies, which have masses M_{1}and M_{2}and centers of mass atR_{1}andR_{2}. Prove that the CM of the whole system is at

[M_{1}R_{1}+M_{2}R_{2}] / [M_{1}+M_{2}]

2. Relevant equations

Definition of CM

3. The attempt at a solution

First I looked at the numerator of the equation given in the problem. If I replaceR_{1}with the definition then M_{1}cancels. The same logic applies to the second term in the numerator. This leaves me with just the summation of all the mr terms for the particles comprising mass 1 and 2 then in the denominator I have the total mass of the system. So the equation given is now in the form of the definition? I feel like this is trivial, but the book has it marked as a harder problem. I feel like I'm missing something and it can't be done this easily. Is my method correct?

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# Homework Help: Center of mass of two extended bodies

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